Abstract

Minority carrier lifetime,, in type-2 strained-layer superlattices (SLSs) and in long-wave (MCT) was measured by optical modulation response technique. It was shown that at 77 K radiative recombination can contribute to the measured values. The Shockley–Read–Hall (SRH) lifetimes were attained as 100 ns, 31 ns, and more than for midwave infrared superlattices, long-wave infrared (LWIR) superlattices, and MCT correspondingly. The nature of the difference between the SRH lifetimes in LWIR superlattice and MCT is discussed.

Received 02 July 2010Accepted 19 July 2010Published online 06 August 2010

Acknowledgments:

LWIR SLS and MCT structures used for measurements were provided by NVESD. The authors are grateful to J. Pellegrino, M. Tidrow, and S. Bandara for helpful discussions and encouragement. This work was supported by NVESD and NSF Award No. DMR071054.